rogers



TELEPHONE.

No. 252,256. Patented Jan. 10,1882.

Jy N UNITED STATES PATENT OFFICE.

JAMES H. ROGERS, OF WASHINGTON, DISTRICT OF COLUMBIA, ASSIGNOR OF ONE-HALF TO FRANK HUMEl AND L. Gr. HINE, BOTH OF SAME PLACE.

TELEPHONE.

SPECIFICATION forming part of Letters Patent No. 252,25,dated January 10,1882. applicationfuedNovembere,1881. (No model.)

`To all whom it may concern:

Beit known that I, JAMES HARRIS ROGERS, aci tizeuof the United States, residingat Washington, in the District ot' Columbia, have invented new and useful 4Improvements in Telephones, ot which the following is a specification.

My invention constitutes an improved telephonie transmitter and receiver. It consists of a core of a sheetof any meta susceptible to the magneticiutlueuce of an electric current, sufficiently thin to be more or less resonant, bent in such manner that its edges approach each other. Around this core, and' parallel with the slit formed by its adjacent edges, I wind a helix, which is placed in the telephonie circuit. I thus con stitute it'an electro-magnet susceptible to variations in the currenttraversing the circuit. The sheet ot'metal zo of which the core is formed may be a permanent magnet. I have found that an instrument so constructed is capable of taking up with facility all electrical vibrations passing through the line and distinctly converting them into '25 sound-waves without the addition oi'any armature, suchas is used in telephones of the usual form. This is due to the increased molecular tension of the metal when bent in the manner.

above mentioned, which renders it highly sen- 3o sitivc to the slightest electrical disturbances, and to the peculiar cylindrical shape, as well as to the large extent ot' resonant surface, whereby its endor mouth reproduces the vibrations together with their edges.

The instrument not only serves as an etticient telephonie receiver, but, on account of its structure, it so responds to theimpact ot' the sound-vibrations created by the voice that igt-causes inductively variations or changes ot' the current on the line corresponding to such vibrations, and thus acts asa transmitter ot' articulate' speech or other sounds. Such in struments, properly connected up in batterycircuit, serve, therefore, as both transmitters and receivers. I would say, however, that the apparatus is most efficient and is more especially designed as a telephonie receiver.

In the accompanying drawings, Figure l is a view of one form of my,improved telephone number of such helices, and may be placed in circuit with one or more transmitters on as many different main lines as may be desired. In Fig. 3 l have shown the core as wound with one helix. This core, it will be observed, is made funnel-shaped or conical in order to increase its resonance and improve its reproduction of sound. The edges or poles of the magnet are preferably brought, without touching, into close proximity to each other'in order to 7o obtain the best results. I have found, however, that the edges may be actually brought into contact and that the instrument will still work as above set forth.

Telephonie receivers constructed as above set forth respond to all the sounds transmitted overfthe circuit and reproduce with facility and distinctness all spoken words, messages, and tones uttered at the transmitter.

My improved telephone is ot' course to be 80 placed in circuitin the most approved manner, as other telephones are. v

It will be seen that Vby my invention I produce a telephonie transmitter and receiver which transmits articulate speech and all the 35 tones of the'liuman voice without the aid ot a vibrating diaphragm, which diaphragm has heretofore` been deemed essential to the practical andsuccessful transmission ot' :articulate speech.

'My instruments may be used togetheras transmitters or receivers, as above mentioned, or they may be used iu connection with any ot'` the wellknown transmitters and receivers new in use.

I do not contue myself to the shape shown, as it is obvious that the core may be made of other shapes, as oval or square in cross-scction, and will still respond to electrical vibrations.

I am aware that it has long been well known that the core of an electro-magnet emits a sound as the current in its helix is made and broken, and that this sound is due to molecular changes in the magnet'cansed by the variation ofthe current. I make no claim, therefore, covering such subject-matter.

I am also aware that it has been proposed -to receive articulate speech upon a magnet having a straight core, the articulation being due to the shortening and lengthening of the core. I believe that speech has been thus received, and I make no claim thereto.

I am also aware that a telephonie receiver consisting ot' a magnet formed of a plate of metal shaped Yso as to bring its edges in close proximity, the helix beingformed parallel with its edges, and of an armature or diaphragm, is shown in a United States patent heretofore granted; but such magnet is shown as made ot' a comparatively heavy and non-resonant plate, and as the receiving-instrnment in which it is shown uses a diaphragm or armature, it

1. The telephone herein described, consisting of a sheet of metal sutciently thin to be more or less resonant and snceptible of magnetic induction, bent as set forth, and havinga helix Wound parallel with its adjacent edges,

said telephone being adapted for the transmission and reception of articulate speech without the use of a diaphragm or armature.

' 2. A telephonie transmitter and receiver conftion of articulate speech without the use of a diaphragm or armature.

In testimony whereof I have hereunto set my hand inthe presence of two subscribing Witnesses.

JAS. H. ROGERS.

Witnesses:

J AMES L. NoRRIs, ALBERT H. NoRRis. 

